5616 Platinum Resistance Thermometer User s Guide

Transcription

1 Hart Scientific 5616 Platinum Resistance Thermometer User s Guide Rev

2 Limited Warranty & Limitation of Liability Each product from Fluke Corporation, Hart Scientific Division ( Hart ) is warranted to be free from defects in material and workmanship under normal use and service. The warranty period is 1 year for the Platinum Resistance Thermometer. The warranty period begins on the date of the shipment. Parts, product repairs, and services are warranted for 90 days. The warranty extends only to the original buyer or end-user customer of a Hart authorized reseller, and does not apply to fuses, disposable batteries or to any other product, which in Hart s opinion, has been misused, altered, neglected, or damaged by accident or abnormal conditions of operation or handling. Hart warrants that software will operate substantially in accordance with its functional specifications for 90 days and that it has been properly recorded on non-defective media. Hart does not warrant that software will be error free or operate without interruption. Hart does not warrant calibrations on the Platinum Resistance Thermometer. Hart authorized resellers shall extend this warranty on new and unused products to end-user customers only but have no authority to extend a greater or different warranty on behalf of Hart. Warranty support is available if product is purchased through a Hart authorized sales outlet or Buyer has paid the applicable international price. Hart reserves the right to invoice Buyer for importation costs of repairs/replacement parts when product purchased in one country is submitted for repair in another country. Hart s warranty obligation is limited, at Hart s option, to refund of the purchase price, free of charge repair, or replacement of a defective product which is returned to a Hart authorized service center within the warranty period. To obtain warranty service, contact your nearest Hart authorized service center or send the product, with a description of the difficulty, postage, and insurance prepaid (FOB Destination), to the nearest Hart authorized service center. Hart assumes no risk for damage in transit. Following warranty repair, the product will be returned to Buyer, transportation prepaid (FOB Destination). If Hart determines that the failure was caused by misuse, alteration, accident or abnormal condition or operation or handling, Hart will provide an estimate or repair costs and obtain authorization before commencing the work. Following repair, the product will be returned to the Buyer transportation prepaid and the Buyer will be billed for the repair and return transportation charges (FOB Shipping Point). THIS WARRANTY IS BUYER S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IM- PLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. HART SHALL NOT BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL. OR CONSE- QUENTIAL DAMAGES OR LOSSES, INCLUDING LOSS OF DATA, WHETHER ARISING FROM BREACH OF WARRANTY OR BASED ON CONTRACT, TORT, RELIANCE OR ANY OTHER THEORY. Since some countries or states do not allow limitation of the term of an implied warranty, or exclusion or limitation of incidental or consequential damages, the limitations and exclusions of this warranty may not apply to every buyer. If any provision of this Warranty is held invalid or unenforceable by a court of competent jurisdiction, such holding will not affect the validity or enforceability of any other provision. Fluke Corporation, Hart Scientific Division 799 E. Utah Valley Drive American Fork, UT USA Phone: Telefax: supporthartscientific.com Subject to change without notice. Copyright 2006 Printed in USA Rev

3 Table of Contents 1 Before You Start Symbols Used Safety Information Warnings Cautions Authorized Service Centers Introduction General Recalibration Specifications Installation Lead Wire Identification PRT Care and Handling Guidelines PRT Care PRT Handling Guidelines Operation General Immersion Requirements Thermal EMF Transition Junction Troubleshooting Troubleshooting i

4 1 Before You Start Symbols Used 1 Before You Start 1.1 Symbols Used Table 1 lists the International Electrical Symbols. Some or all of these symbols may be used on the instrument or in this guide. Table 1 International Electrical Symbols Symbol Description AC (Alternating Current) AC-DC Battery CE Complies with European Union Directives DC Double Insulated Electric Shock Fuse PE Ground Hot Surface (Burn Hazard) Read the User s Manual (Important Information) Off On Canadian Standards Association 1

5 5616 PRT User s Guide Symbol Description OVERVOLTAGE (Installation) CATEGORY II, Pollution Degree 2 per IEC refers to the level of Impulse Withstand Voltage protection provided. Equipment of OVERVOLTAGE CATEGORY II is energy-consuming equipment to be supplied from the fixed installation. Examples include household, office, and laboratory appliances. C-TIC Australian EMC Mark The European Waste Electrical and Electronic Equipment (WEEE) Directive (2002/96/EC) mark. 1.2 Safety Information Use this instrument only as specified in this guide. Otherwise, the protection provided by the instrument may be impaired. The following definitions apply to the terms Warning and Caution. Warning identifies conditions and actions that may pose hazards to the user. Caution identifies conditions and actions that may damage the instrument being used Warnings To avoid personal injury, follow these guidelines. DO NOT use this instrument to measure the temperature of any hazardous live component. Use of this instrument at high temperatures for extended periods of time can cause the handle to become hot. Follow all safety guidelines listed in the user s guide. Calibration Equipment should only be used by Trained Personnel Cautions To avoid possible damage to the instrument, follow these guidelines. DO NOT drop or bang the probe in any way. This will cause damage to the probe internally and affect its calibration. Read Section entitled PRT Care and Handling Guidelines before removing the PRT from the shipping box. Incorrect handling can damage the PRT and void the warranty. Keep the shipping container in case it is necessary to ship the PRT. Incorrect packaging of the PRT for shipment can cause irreparable damage. 2

6 1 Before You Start Authorized Service Centers 1.3 Authorized Service Centers Please contact one of the following authorized Service Centers to coordinate service on your Hart product: Fluke Corporation, Hart Scientific Division 799 E. Utah Valley Drive American Fork, UT USA Phone: Telefax: supporthartscientific.com Fluke Nederland B.V. Customer Support Services Science Park Eindhoven EC Son NETHERLANDS Phone: Telefax: ServiceDeskfluke.nl Fluke Int'l Corporation Service Center - Instrimpex Room 2301 Sciteck Tower 22 Jianguomenwai Dajie Chao Yang District Beijing , PRC CHINA Phone: Telefax: xingye.hanfluke.com.cn Fluke South East Asia Pte Ltd. Fluke ASEAN Regional Office Service Center 3

7 5616 PRT User s Guide 60 Alexandra Terrace #03-16 The Comtech (Lobby D) SINGAPORE Phone: Telefax: antngsinga.fluke.com When contacting these Service Centers for support, please have the following information available: Model Number Serial Number Complete description of the problem 4

8 2 Introduction General 2 Introduction 2.1 General The Platinum Resistance Thermometer (PRT) model 5616 is designed to be a secondary standard interpolating instrument converting temperature to resistance. The 5616 may also be used as a temperature standard for calibration of industrial sensors. The PRT is used with a readout device to detect temperature changes or actual temperature. 2.2 Recalibration The recalibration of the 5616 PRT should be scheduled according to the user s company Quality Assurance requirements. Normally, a PRT is recalibrated annually. Unless the PRT is used only over a limited range, calibration over the full range of the PRT is recommended. For information on recalibrating your 5616, contact an Authorized Service Center for an RMA number and current pricing (see Section 1.3, Authorized Service Centers). Depending on the user s Quality Assurance requirements, the PRT drift should be checked periodically at the Triple Point of Water (TPW). Section 7, Troubleshooting, provides information on drift with respect to mechanical shock and oxidation. 5

9 3 Specifications 3 Specifications Parameter Value Temperature range 200 C to 420 C Nominal resistance at 0.01 C Temperature coefficient Accuracy [1] 100 Ω ±0.5Ω Ω/Ω/ C nominal See footnote Short-term repeatability [2] ± C at C Drift [3] ± C at C Hysteresis Sensor length Sensor location Sheath dimensions, length x diameter Sheath diameter tolerance ± C maximum 50.8 mm (2.0 in) 9.5 mm ± 3.2 mm from tip (0.375 in ± in) mm x 6.35 mm ( in x in) ±0.08mm(±0.003in) Sheath material Inconel 600 Minimum insulation resistance 500 MΩ at 23 C Transition junction 50 C to 150 C temperature range [4] Transition junction dimensions Minimum immersion length [5] (< 5 mk error) Maximum immersion length Response time [5] Self heating (in 0 C bath) Lead-wire cable type Lead-wire length 76.2 mm x 9.5 mm (3.00 in x in) 102 mm (4.0 in) 254 mm (10 in) 8 seconds typical 60 mw/ C Lead-wire temperature range 50 C to 150 C Calibration Teflon jacketed cable, Teflon insulated conductors, 24 AWG stranded, silver plated copper cm ± 2.5 cm (72.0 in ± 1.0 in) NIST-traceable calibration [1] "Accuracy" is a difficult term when used to describe a resistance thermometer. The simplest way to derive basic accuracy is to combine the probe drift specification and calibration uncertainty with readout accuracy at a given temperature. [2] Three thermal cycles from min to max temp, includes hysteresis, 99.8 % confidence [3] After 100 hrs at max temp, 99.8 % confidence [4] Temperatures outside this range will cause irreparable damage. For best performance, transition junction should not be too hot to touch. [5] Per ASTM E 644 7

10 4 Installation Lead Wire Identification 4 Installation 4.1 Lead Wire Identification The 5616 PRT is equipped with a four-wire cable (see Figure 1). Four lead wires are used to cancel lead wire resistance. For best results, the readout device should be equipped to handle four-terminal resistors. The lead wires are two different colors. Lead wire pairs attached to each end of the sensor are identified by red and white insulation. White Red White Figure 1 PRT Schematic Red 9

11 5 PRT Care and Handling Guidelines PRT Care 5 PRT Care and Handling Guidelines 5.1 PRT Care CAUTION: READ THIS SECTION BEFORE REMOVING THE PRT FROM THE SHIPPING BOX OR CASE Care must be taken in handling the PRT to maintain calibration accuracy. Care should still be used when handling the PRT even though the Inconel sheath is durable and provides good protection for the sensor. Correct handling of the PRT will prolong the life expectancy. When not in use, the PRT should be stored in an optional protective case that can be purchased by contacting an Authorized Service Center (see section 1.3, Authorized Service Centers). The handle is not designed to be immersed. 5.2 PRT Handling Guidelines DO keep the thermometer as clean as possible. DO immerse the thermometer in the appropriate liquid for the temperature range. If a dry block is used, the well diameter should allow the PRT to comfortably slip in and out without excess movement. For best results, immerse the thermometer as deep as possible to avoid stem effect (the temperature error caused by the conduction of heat away from the sensor). DO allow sufficient time for the thermometer to stabilize before making measurements. This allows for the best accuracy. DO use the correct drive current with the thermometer to prevent error in temperature or resistance. Hart Scientific recommends 1mA. DO use the protective shipping box provided or other protection when the thermometer is not in use. DO NOT subject the thermometer to any physical shock or vibration. DO NOT use pliers or other devices to squeeze the sheath. This action can permanently damage the PRT. DO NOT subject the thermometer to temperatures above the highest specified operating temperature. DO NOT expose the thermometer s handle or cables to extreme temperatures. DO NOT screw a clamp down so tight that it dents the sheath. This can permanently damage the PRT. 11

12 6 Operation General 6 Operation 6.1 General For best results, be familiar with the operation of the heat source and the readout instrument. Be sure to follow the manufacturer s instructions for the readout instrument and the heat source. 6.2 Immersion Requirements Stem effect can cause measurement errors for any thermometer. This error is due to heat lost or gained by the sensing element through the thermometer stem. In addition, heat losses occur due to radiation losses from the sensing element to the housing. The immersion depth for standards is dependent on several factors including accuracy requirements and type of liquid. However, remember the handle limitations. The handle is not designed to be immersed. The exact immersion depth required can be determined by performing a gradient test taking measurements approximately every 1.27 cm (0.50 inches) until there is a significant difference in readings. Allow the thermometer to stabilize at each new depth. Plot the results to see the stem effect. 6.3 Thermal EMF Two factors contribute to thermal EMF, chemical consistency and physical consistency. Variations in chemical structure due to impurities can contribute to thermal EMF. Also discrepancies in crystal structure can contribute to thermal EMF. These factors are minimized by annealing the full length of wire before construction of the PRT. Likewise, connection to extension lead wires and readout instruments can be a source of thermal EMF. The thermal EMF is caused by a difference in temperature between two connections. If the two connections are the same temperature, there will be little or no thermal EMF effects. However, if there is a substantial temperature difference between connections, the thermal EMF effects will be significant. Therefore, cover or insulate any exposed bridge or galvanometer terminals to lessen the source of error. The effects of thermal EMF can be canceled by using an AC bridge or a DC bridge with reversible current. 6.4 Transition Junction Exceeding the temperature range of the transition junction will cause a breach in the seal of the instrument. Maintaining the seal is critical to preventing moisture from entering the device. If moisture penetrates the seal, the PRT's short term repeatability, hysteresis, and insulation resistance may be adversely affected. Insulation resistance also decreases rapidly as the transition junction 13

13 5616 PRT User s Guide temperature increases, even if the seal is not broken. When the insulation resistance becomes sufficiently low, performance suffers. A good rule of thumb is that the transition junction is too hot when it is hot enough to burn your thumb. 14

14 7 Troubleshooting Troubleshooting 7 Troubleshooting 7.1 Troubleshooting In the event that the probe appears to function abnormally, this section may be of use in solving the problem. Several possible problem conditions are described along with likely causes and solutions. If a problem arises, please read this section carefully and attempt to understand and solve the problem. If the probe seems faulty or the problem cannot otherwise be solved, contact an Authorized Service Center (see Section 1.3) for assistance. Be sure to have the model number and serial number of your probe available. Problem Data changes greater than 0.1 C are observed Data changes less than 0.1 C Data unstable Temperature readout different than expected, e.g. the heat source is set at 150 C, the PRT measures 125 C. Causes and Solutions Mechanical shock can cause temperature errors as great as 0.5 C. If this is observed, first measure and record the Rtpw. Slight mechanical shock can cause temperature errors less than 0.1 C. If the data is unstable at the Triple Point of Water (TPW), check connections for evidence of a bad connection. If the connector appears to be in good condition and the connections are good, the PRT may be damaged. Contact an Authorized Service Center (see Section 1.3). If the data is unstable at high temperatures, it may be due to electrical noise in the system. Reduce the temperature and observe the data. If it is stable, electrical noise is interfering with the measurements at high temperatures. Also, this is usually due to low shunt resistance. The resistance between the leads and the sheath (shunt resistance or insulation resistance) as measured by a resistance meter should be greater than 500 megohms at room temperature. Check the grounding of the readout device and the heat source. A faulty ground on either device could interfere with high temperature measurements. A ground wire attached to the metal sheath of the PRT may help to reduce electrical noise interference. Measure the PRT resistance at TPW. If the resistance of the PRT is less than the rated resistance, e.g. 98 ohms for a 100 ohm PRT, there may be a short in the sensor. If the resistance of the PRT is only a few ohms, there may be a short in the four lead-wires. If the PRT is open, the resistance will be Out of Limits or in the kilohm or megohm range. For more information or assistance, contact an Authorized Service Center (see Section 1.3). 15